Management of preterm idiopathic oligohydramnios and pregnancy outcome

Objective To explore the management and pregnancy outcome of preterm idiopathic oligohydramnios and their relationships. Methods The women with a singleton term pregnancy received ultrasound examinations at 28- 36+ 6gestational weeks in our hospital from 2009 to 2013. The pregnancies were divided into three groups according to amniotic fluid index( AFI) : oligohydramnios group( AFI≤5 cm),borderline group( AFI 5. 1- 8. 0 cm) and normal group( AFI 8. 1- 18cm). Women with decreased AFI received treatment of intravenous and / or oral hydration. The effect of hydration,pregnancy outcome and the association between them were assessed. Results 1pregnant women: The effective rate of hydration was 51. 35%. Hydration prolonged gestational weeks significantly in borderline group. Oligohydramnios group had a higher rate of premature delivery with 37. 04%,most of which were iatrogenic preterm delivery. Women with decreased AFI also had a higher rate of cesarean section( CS) and labor induction. 2perinatal fetus: The incidence of adverse perinatal outcomes was significantly higher in oligohydramnios group. Neonatal birth weight was significantly lower in fetus whose mother with decrease AFI,especially much lower with isolated oligohydramnios. These differences were eliminated when women with decreased AFI delivered at term. There was no correlation between effective treatment and the rate of new onset pregnancy complications and CS,but a lower rate of premature delivery and adverse perinatal outcome and increased neonatal birth weight. Conclusion The effective hydration may improve the pregnancy outcome in women with decreased AFI especially with isolated oligohydramnios. Effective hydration and delivery at term may be a useful index to predict improved pregnancy outcome in isolated oligohydramnios diagnosed before 37 gestational weeks.